How does being forced to replay over the same missions make a game 'feel more alive'? This makes no sense to me except for being annoying repetitious.

It depends on the game. Where this would take days in a game like GTA4, it was only a few hours in Dead Rising (again, much easier because you keep the experience points).

Dead Rising isn't really a game that should be compared to GTA just because it's an open world game. It's much closer to old-timey arcade games that you could replay without getting sick of them. The first time through might take you days but, as you got better at them, later playthroughs could be done in a sitting. Dead Rising sorta strikes balance between the two.

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It's better to be dead and cool than alive and uncool.

I meant that in many of the 'sandbox' games the clock starst ticking only after you take the mission.
There is war or whatever happening and you can play pool at local bar without any worries or need to help your friends.

In DR you need to help people or they will die, for me the need for choices is a good thing.

Just got done playing. Runs well and doesn't look as bad as the screenshots posted in this thread. It definitely doesn't look great, but with this amount of zombies on screen I am fine with it. 3D vision is broken at the moment... the left eye will see double for some reason.